1. Field of the Invention
The present invention relates to an image pickup apparatus which detects and corrects amounts of image blur of an object image in a translation direction and a rotation direction, and an image stabilization method.
2. Description of the Related Art
Recently, cameras equipped with an image stabilization function have been common, and it has become possible to obtain a photographed image without image blur without especially paying attention in hand-held photographing.
Further, there are lens interchangeable cameras in which a taking lens is changeable according to photographing purposes. There are mainly two types of such a camera: a type in which an interchangeable lens is equipped with the image stabilization function described above and a type in which a camera body is equipped with the image stabilization function (however, both of the interchangeable lens and the camera body may be equipped with the function).
In the case where the interchangeable lens is equipped with the image stabilization function, a sensor configured to detect a motion applied to the interchangeable lens (and, therefore, the camera body integrally coupled with the interchangeable lens) is provided in the interchangeable lens, and image blur is corrected by moving a part of a taking lens group on a plane orthogonal to an optical axis in such a direction that offsets image blur caused by the detected motion.
On the other hand, in the case where the camera body is equipped with the image stabilization function, a sensor configured to detect a motion applied to the camera body is provided in the camera body, and image blur is corrected by moving an image pickup device in such a direction that offsets image blur caused by the detected motion.
Further, a movie is acquired in various methods such as hand-held still photographing, panning photographing, walking photographing and photographing from a transportation vehicle such as an automobile and a train. Since characteristics of blur caused in a movie differ according to which method photographing has been performed, a correction range and a processing method optimal for image stabilization differ.
For example, since a blur angle in walking photographing is larger than in still photographing, a correction range optimal for hand-held still photographing is an insufficient range in walking photographing, and it becomes difficult to acquire a movie with little blur.
As a technique paying attention to such a point, for example, Japanese Patent Application Laid-Open Publication No. 2014-206660 describes a technique in which, as an example of control of a camera including a lens capable of image stabilization, whether the camera is in a walking state or not is judged based on a rotational blur detected by an angular velocity sensor and a translational blur detected by an acceleration sensor, and a range of image stabilization by a lens is caused to be wider at the time in a walking state than at the time in a non-walking state.